1. Field of the Invention
The present invention relates to an electrical connector, and particularly to an electrical connector for engaging with a printed circuit board which is oriented in a horizontal aspect, wherein a force for effecting a connection between the connector and the board can be controlled in a required range.
2. Description of Related Art
Referring to FIGS. 8 and 9, a conventional electrical connector 7 is shown to interconnect a first printed circuit board (PCB) 8 arranged in a horizontal aspect and a second printed circuit board 9 arranged in a vertical aspect. The electrical connector 7 comprises a dielectric housing 70 and a plurality of terminals received in the dielectric housing 70. The terminals are divided into first terminals 72, and second terminals 74 which generally perform mechanical counterbalance function rather than electrical transmission one, wherein the first terminals 72 extend out of upper and bottom surfaces of the dielectric housing 70, and the second terminals 74 extend out of the bottom surface of the dielectric housing 70. The first PCB 8 has a bottom of face engaging with an arced top portion of each the first terminals 72 by a depressing normal force F0 acting on the PCB 8. The second PCB 9 is inserted between lower parts of the first and second terminals 72, 74 extending beyond the bottom surface of the housing 70.
A relation between a downward displacement of the first PCB 8 and the depressing normal force F0 is shown in FIG. 9, in which the displacement of the PCB 8 equals to a downward displacement of the first terminals 72, and the depressing normal force F0 equals to a generated reaction force of the fist terminals 72. From FIG. 9, it can be seen that for the conventional connector, the required depressing normal force F0 needs to steeply increase between the requirement minimal and maximal displacements D1, D2 of the first printed circuit board 8. The steep increase of the required depressing normal force F0 can result in a short life of use of the connector 7. Hence, an improved electrical connector is required to overcome the disadvantages of the prior art.
Accordingly, the object of the present invention is to provide an electrical connector which controls normal force required for effectively engaging a PCB in a required range, in other words, regarding a definite displacement of contacts arranged in the electrical connector, the normal force only increases slightly in comparison with the prior art.
In order to achieve the object set forth, an electrical connector is adapted for connecting two PCBs disposed vertical to each other, includes an insulative housing, a plurality of main contacts and assistant contacts. The insulative housing has a lateral wall, a plurality of sidewalls extending from the lateral wall and a plurality of cavities formed between each two adjacent sidewalls. The insulative housing further defines an upper surface and a bottom surface. The main contacts are received in the insulative housing and project upwardly from the upper surface and downwardly from the bottom surface of the housing. Each of the main contacts has a first engaging portion engaging with the housing, and a curved contact portion projecting upwardly beyond the upper surface. The curved contact portion further has a free end in the housing. The assistant contacts are received in the housing, each of which includes a second engaging portion for engaging with the housing and a downwardly slanted bearing portion. The bearing portion engages with the free end of the main contact when a normal force depressed on the contact portion of the main contact.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.